The invention relates to a feed pump, in particular a fuel pump, with a driven impeller rotating between two casing parts and carrying guide vanes delimiting at least one ring of vane chambers, with a part-annular channel arranged in the region of the vane chambers in the casing parts and extending from an inlet duct to an outlet duct, and with a fixed molding arranged on the outer circumference of the impeller, the molding having a recess adjacent to the part-annular channel.
Such a feed pump, designed as a peripheral pump, is known, for example, from DE 43 33 204 C2. In this feed pump, guide vanes arranged on both sides of the impeller are arranged on the outer circumference. The molding has a radially inward-pointing edge axially delimiting two recesses. This edge is located opposite the outer boundaries of guide vanes. DE 196 07 573 A1 discloses a feed pump, in which one edge of the impeller and one edge of the molding are located opposite one another.
These feed pumps have the disadvantage that the guide vanes have only a very small configuration in relation to the total cross-sectional area of the part-annular channel, of the recess and of the vane chambers. As a result, only a very low momentum can be transmitted to the flow to be conveyed. The feed pumps consequently have particularly low efficiency.
The problem on which the invention is based is to configure a feed pump of the type initially mentioned, in such a way that it has particularly high efficiency.